Results 21 to 30 of about 3,951 (191)
Beat frequency quartz-enhanced photoacoustic spectroscopy for fast and calibration-free continuous trace-gas monitoring [PDF]
Nature Communications, 2017 Quartz-enhanced photoacoustic spectroscopy is a sensitive gas detection method whereby radiation-induced sound waves from gas absorption are detected. Here, Wuet al. use the beat frequency between a modulated laser and a tuning fork resonance to increase
Hongpeng Wu +9 more
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Quartz Enhanced Photoacoustic Spectroscopy Based Trace Gas Sensors Using Different Quartz Tuning Forks [PDF]
Sensors, 2015 A sensitive trace gas sensor platform based on quartz-enhanced photoacoustic spectroscopy (QEPAS) is reported. A 1.395 μm continuous wave (CW), distributed feedback pigtailed diode laser was used as the excitation source and H2O was selected as the ...
Yufei Ma +5 more
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A High Sensitivity Preamplifier for Quartz Tuning Forks in QEPAS (Quartz Enhanced PhotoAcoustic Spectroscopy) Applications [PDF]
Sensors, 2017 All the preamplifiers dedicated for Quartz Enhanced PhotoAcoustic Spectroscopy (QEPAS) applications that have so far been reported in the literature have been based on operational amplifiers working in transimpedance configurations.
Tomasz Starecki, Piotr Z. Wieczorek
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Quartz-enhanced laser spectroscopy sensing [PDF]
Light: Science & ApplicationsGas sensing technology is widely applied in various fields, including environmental monitoring, industrial process control, medical diagnostics, safety warnings, and more.
Shunda Qiao +5 more
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Quartz-enhanced photoacoustic spectroscopy [PDF]
Optics Letters, 2002 A new approach to detecting a weak photoacoustic signal in a gas medium is described. Instead of a gas-filled resonant acoustic cavity, the sound energy is accumulated in a high- Q crystal element. Feasibility experiments utilizing a quartz-watch tuning fork demonstrate a sensitivity of 1.2x10(-7) cm(-1) W/ radicalHz .
A A, Kosterev +3 more
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Recent Advances in QEPAS and QEPTS Based Trace Gas Sensing: A Review
Frontiers in Physics, 2020 This invited review paper summarizes and discusses developments of QTF based state-of-the-art quartz-enhanced photoacoustic spectroscopy (QEPAS) and quartz-enhanced photothermal spectroscopy (QEPTS) gas sensing techniques over the past 3 years.
Yufei Ma
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Highly Sensitive Trace Gas Detection Based on In-Plane Single-Quartz-Enhanced Dual Spectroscopy
Sensors, 2022 For this invited manuscript, an in-plane single-quartz-enhanced dual spectroscopy (IP-SQEDS)-based trace gas sensor was demonstrated for the first time.
Tiantian Liang +3 more
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Multi-quartz-enhanced photoacoustic spectroscopy [PDF]
Applied Physics Letters, 2015 A multi-quartz-enhanced photoacoustic spectroscopy (M-QEPAS) sensor system for trace gas detection is reported. Instead of a single quartz tuning fork (QTF) as used in QEPAS technique, a dual QTF sensor platform was adopted in M-QEPAS to increase the signal strength by the addition of the detected QEPAS signals.
Ma, Yufei +7 more
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Improved Tuning Fork for Terahertz Quartz-Enhanced Photoacoustic Spectroscopy. [PDF]
Sensors (Basel), 2016 We report on a quartz-enhanced photoacoustic (QEPAS) sensor for methanol (CH3OH) detection employing a novel quartz tuning fork (QTF), specifically designed to enhance the QEPAS sensing performance in the terahertz (THz) spectral range. A discussion of the QTF properties in terms of resonance frequency, quality factor and acousto-electric transduction ...
Sampaolo A +8 more
europepmc +6 more sources
Photoacoustics, 2022 In this paper, a highly sensitive and integrated near-infrared CO2 sensor was developed based on quartz-enhanced photoacoustic spectroscopy (QEPAS).
Yihua Liu +9 more
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